The photos are a bit blurred but looking at the shape and size of the targets (the white bits on the bum) I think I can see what looks like a small "tail"on the left hand deer, this looks like the “anal tush” this is how you distinguish a female Roe deer from a male once he has cast his antlers. As I can see no tush on the right hand deer and given the time of year. I would say that this is either the female’s kid from last May or it is brother and Sister from last May. Mum will have scampered away as the older deer are usually a bit more wary than the young ones.
On a red deer the white bum is usually off white, it has a bit of a yellow tinge, if the colouring is pure white it is not a Red, it also extends from the bum up onto the end of the back, red also have a black line running down the middle of the back and a tail that is around 7”ish long.
ATB
Tahr